Illness prevention and treatment

What’s your personal breast cancer risk?

Understanding your risk of breast cancer can help you and your doctor prevent it, or find it and treat it.

We know vastly more about breast cancer now than we did 15 years ago. This has led to earlier, more precise diagnoses, and personalized treatment that saves lives while limiting the toll cancer takes upon women and their families.

Your risk for breast cancer is highly personal, arising from some factors that you can’t control, such as your genetic makeup, and some factors that you can. Having risk factors doesn’t mean you will inevitably develop breast cancer: Many women with risk factors never develop breast cancer. On the other hand, women with no apparent risk factors can also develop breast cancer. But managing controllable breast cancer risk factors can make a positive difference to your overall health, not just your breast cancer risk.

Knowing more about your personal risk can help you, along with your doctor, plan customized screening and other preventative measures.

Know your family history

Start by looking at your family history, which is an important risk factor for breast cancer. All breast cancer is “genetic” – caused by gene mutations – but only 10% of those mutations are hereditary. Angelina Jolie’s courageous declaration that she had a preventive double mastectomy after testing positive for the BRCA1 mutation was prompted by her knowledge of her family history of cancer, and her desire to help others reduce their risk through understanding their family histories. However, if there is breast cancer in your family, it is most likely not hereditary.

Your family history of cancer should include all known affected individuals – not just 1st-degree relatives (parents, siblings, children) – and the approximate age at which they were diagnosed with any type of cancer, including breast and ovarian cancer. The risk of breast cancer increases with age, and you should make a note of relatives who were diagnosed before menopause (about age 50). Medical experts can review and assess potential risks related to your family history of cancer, answer your questions and offer advice.

Regular physical activity seems to reduce the risk of breast cancer, particularly in postmenopausal women. Eating a diet high in plants and healthy oils may also reduce breast cancer risk. Although there is concern that exposure to chemicals and toxins may increase the risk of breast cancer, there is no direct evidence of this link.

Screening for breast cancer

Breast cancer screening is used to check for early signs of cancer in women who have no symptoms or signs of breast cancer. Recommendations for screening continue to be updated, and differ depending on your personal profile, including your age and family history.

For each type of medical screening, the benefits must be balanced against potential harm including false positive results, over-diagnosis and over-treatment.

Breast examinations. Most experts feel that breast exams by a medical professional (or self-exams) do not add value for women who do not have breast complaints, as there is no evidence that they decrease the death rate from breast cancer.

Mammography. The main type of screening for breast cancer, mammography, allows early detection of breast cancer. The main drawbacks are false positives. Previously, women were advised to have “universal screening” mammograms starting at age 40, but these recommendations have changed towards a more personalized screening regimen. In Canada, current recommendations are for women of average risk for breast cancer to have mammograms every 2-3 years from age 50-74.

Breast MRIs. Magnetic resonance imaging of the breast is only used in addition to mammograms to screen women at high risk for breast cancer, such as those who are BRCA1 or BRCA2 positive. They are not recommended for women who at moderate or lower risk, partly due to the associated false positive results.

So get to know your personal risk profile for breast cancer, take the time to discuss it with your health care provider and keep informed. As knowledge advances, medical recommendations for breast cancer screening, prevention, diagnosis and treatment will continue to evolve.